Fluid transfer apparatus



y v w. TQTABB 2,318,128 I FLUID TRANSFER APPARATUS Original Filed Oct;22, 1940 2 Sheefs-Sheet 1 f as 41 4g 5 g 40 13 f5 27 3 3 7 7 1.. 4 v t--I 55 a2 it 7 I '15 15 I 64 '11 10 l; 25 y v 30 I INVENTbRQ 9 ikz I i I I1' l'fdrflzr i v V HTTOIP/VE'YS zrmwwmam w. T. TABB 8, 8 FLUID TRANSFERAPPARATUS May 4, 1943.

2 Sheets-Sheet 2 Original Filed 001:. 22, 1940 Mb P INVENTOR. fikrmr T7&h5 BY Patented May 4, 1943 FLUID TRANSFER APPARATUS Warner T. Tabb,Brooklyn, N. Y., assignor to Eisemann Magneto Corporation, New York, N.Y., a corporation of New York Original application October 22, 1940,.Serial No. 362,179. Divided and this application March 17,

1942, Serial No. 435,118

6 Claims. (Cl. 103-207) The present invention relates to fluid transferapparatus and more particularly to pump apparatus adapted to effecttransfer of-iluids either liquid or gaseous for a variety of purposes,as disclosed in my parent application Serial No. 362,179, filed October22, 1940, of which the present application is a division.

General objects of the invention are the provisions of such apparatuswhich is of simple and economical construction with minimization ofleakage tendencies, requires little if any careful and costly machiningand treating of cooperating parts frictional engagement between which isrelatively minimized thus reducing tendency of wear which mighteventually require replacements or repair, can be readily and easilyassembled and disassembled, is eflicient in operation to transfer fluideffectively at a relatively uniform rate, and is capable of efficienthigh frequency operation; and structuralembodiments of such apparatuswhich can readily and economically be made and assembled in massproduction while assuring efficient use and operation thereof.

More specific objects of the invention are the provision of suchapparatus characterized by a pump chamber formed 'by cooperation of acasing and a diaphragm having lateral rigidity and certain springcharacteristics with diaphragm biasing' leaf-like spring structurehaving certain spring characteristics mounted in the chamber in a mannerto provide certain net spring characteristics for combined diaphragm andspring construction; and to provide such apparatus wherein the mountingand characteristics of said diaphragm structure are such that anoutwardly projecting diaphragm operating member mounted on the diaphragmis properly and efiiciently guided in its operation withoutnecessitating use therefor of bearing supports or like guiding meanswhich might tend to introduce undesirable problems of construction,manufacture and wear; and which assure eflicient operation of saidapparatus by mechanical means that may tend in operation to flex saiddiaphragm only inwardly.

. Another object of the invention is the provision in such apparatus ofsuitable fluid passages past a diaphragm biasing spring disc structurewithin the pump chamber of such a diaphragm pump, either through thediaphragm or around the periphery thereof, which assures emcient use andoperation thereof.

A still'further objectof the invention is to provide such diaphragmapparatus of such construction as to permit easy and economicalprovision of simple and effective priming means,

manually operable if desired, which requires no particular provision ofpacking to prevent leakage, which can be. simply mounted and demountedwithout affecting assembly of other parts, and which can be manipulatedeffectively to discontinue transfer operation of the pump apparatuswithout disturbing mechanical means effecting such transfer operation.

Other objects of the invention will-in part be obvious and will inpartappear hereinafter.

The invention accordingly comprises the features of construction,combination of elements and arrangement of parts, which will beexemplified in the construction hereinafter set forth and the scope ofthe invention will be indicated in the claims;

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawings, in which: I

Fig. l is a top plan view of one embodiment of the apparatus of thepresent invention;

Fig. 2 is a sectional view taken on line 2-2 of Fig. 1;

Fig. 3 is a top plan view of the structure shown in Figs. 1 and 2 butwith parts removed and broken away; and r Fig. {l is a sectional viewtaken on line 4-4 of Fig. 1.

Various diaphragm pump structures have been proposed for use intransferring fluids, both gaseous and liquid. For example, suchstructures have been proposed for use in both mechanical and electricalgasoline injection systems as well as for use in fuel supply systems ofinternal com-' bustion engines of the Diesel type, oil .bumers and thelike. Many of such structures, however, have been of such, constructionas to require extremely careful and costly machining and fittingofparts, treating of material to harden frictionally engaging parts, andcostly and frequently ineflicient provisions of packing to preventleakage; and have been complicated making assembly and disassemblydifllcult, subject to wear of frictionally engaging parts making repairor replacement of parts eventually necessary, and inemcient andnon-uniform in operation. Further, such structures have been such as tomake their use in systems requiring high speed operation, for examplefuel supply systems for internal combustion engines, extremely uncertainand unsuitable.

These and other difflculties are efliciently alleviated by the apparatusof the present invention for use, by way of example, in fuel supplysystems for Diesel engines. The diaphragm pump structure of theinvention has no'working parts characterized by frictional engagement ofguiding bearings, other than a roller. if desired, used as a camfollower to impart movement to a diaphragm operating member or rod. Thediaphragm operating member is-preferably anchored to the diaphragm toproject outwardly therefrom free from any bearing support. It is guidedin its operation solely by the diaphragm having lateral rigidity mountedwith peripheral portions thereof seated on a casing cooperating with theformer action.

Provision is made. for manually or otherwise 1 priming the apparatus.This is accomplished by means exterior of the chamber whereby necessityfor packing andtendency of leakage are eliminated. Suitable mechanismpermits raising or moving inwardly the diaphragm operating member.Preferably a member or shaft is rotatably mounted on the apparatusexteriorly of the chamber preferably on a base member supporting thediaphragm and casing. The inner end thereof which has been found to behighly satisfactory ture with an interposed washer 24 and suitablegasket rings 25, 25. 1

The base member I0 is provided centrally with a hole 26 larger than theoperating rod l1 and the roller I! carried thereby to permit withoutcontact free reciprocation of the latter therethrough.

The diaphragm l2 and the casing 14 cooperate toprovide a pump chamber 21on the side walls of which are formed a plurality of circumferentiallyspaced seats 2828 providing a plurality of intermediate fluid passages29-29 past the seats 28-28. A diaphragm biasing leaf-like springstructure 30, preferably formed of one or more laminae of sheet steel ofdisc configuration is mounted in the chamber 21 with its peripherysupported on the seats 2828 preferably with at least small lateralclearance. This spring structure 30 is provided'with a central aperture3| which engages over the inner end 22 of the operating rod and thestructure mounted thereon preferably receiving the nut 23 with at leastsmall lateral clearance at points of greatest lateral dimension with theportions adjacent the aperture may be-provided with a cam or the like orso shaped as to. engage means such as a shoulder on the operating rodtoimpart to the latter the desired movement when the priming member orshaft is rotated. When operating the apparatus by a cam with the outerend of the operating rod biased tothe external surface thereof to act asa cam follower the priming mechanism may be utilized to arrest fluidtransfer operation of the apparatus merely by rotating the shaft andholding it in rotated position to raise the cam follower free from thecam and hold it in raised position.

Referring to the drawings like numerals refer to like parts throughout.A base member or plate I is provided with an annular seat H upon whichseats the periphery of a diaphragm l2. The diaphragm l2 may comprise oneor more laminae of sheet steel and preferably has a gasket ring 13located on either side of the periphery thereof. A casing 14 of generalcup-shape and preferably domed at the top has an annular seating surfacel5 adapted to cooperate with the seat Ii onthe base III to clamp thediaphragm l2 and gaskets I3, l3therebetween in a fluid-tight manner,suitable screws I6IG1 being used to clamp the parts together.

An operating member or a rod I1 is anchored centrally to the diaphragml2 to project outwardly therefrom. This member preferably comprises afork l8 between the legs of which is rotatably mounted a roller l9constituting a cam follower adapted to ride on the outer surface of acam 20. A flange 2! at the base ofthe operating member I! provides abearing shoulder for a central portion. of the diaphragm l2 and an innerstud end 22 thereof projects through a central aperture in the diaphragmI2 and is externally threaded to receive a nut 23 between which and theflange 2i is clamped the diaphragm strucbearing against the washer 24 toform a biasing abutment for the diaphragm structure.

This spring structure 30 may be cupped and positioned as shown in thedrawings. Obviously the position of the spring structure 30 may bereversed provided the seats 28-28 and the diaphragm structure oranchorage structure of the operating rod are suitably altered toaccommodate such reversal. The position and shape of the springstructure will be largely dictated by the results desired, thedimensions such as relation of thickness of spring structure todiameter, degree of initial cupping, etc. For some purposessubstantially flat disc spring structure may be desirable, such as wherethe diaphragm is to be flexed in opposite directions from anintermediate neutral position which may be determined by a substantiallyflat diaphragm in the assembly when not stressed. Equalization of suchtravel results in the least strain on the diaphragm. The use of a flatspring structure assures compactness of pump construction.

A flat or initially uncupped diaphragm, such as that shown by way ofexample in the drawings,

has certain well defined characteristics asi a spring in and of itself.These are such as may tend to result in excessive pressure of the camfollower against thecam in the positions of maximum flexure of thediaphragm, such as the innermost position of the diaphragm andassociated parts of the structure shown in the drawings. Further in sucha, structure those characteristics may tend to prevent the cam followerfrom effectively following the cam in the outermost position of thediaphragm. The plotted curve of those diaphragm characteristics is foundto be of great curvature indicating that the rate of change of positiveand negative pressures may be of an objectionable degree, under certainconditions making it advisable to use very small diaphragm deflections.

This may be compensated for or effectively corrected by the use of aninitially cupped spring which has a reverse spring characteristic curve.Net spring characteristics of the combination of such diaphragm andspring structure can thus be obtained which will assure approximatelyuniform pressure of the cam follower on the cam. Even a less pressure inthe innermost position of the diaphragm than in the neutral or outermost.positions thereof, on greater pressure in the latter position than whenin the neutral position,

may be attained by proper predetermined combinations. Thus the springrigging of the pres-' ent pump construction while making for simple andcompact pump construction assures long life for the diaphragm and itsoperating mechanism and efiicient pump performance with the by a similarcap 4| on the outlet side. The

chambers 31 and constitute the inner ends of the inlet and outlet fluidpassages communicating with the pump chamber 21 through suitable valvestructure located therein. These valves preferably are of the checkvalve type so mounted in their respective chambers as to permit fluid.to flow into the pump chamber 21 from the inlet side and fluid to flowout of the pump chamber on the outlet side, as indicated in thedrawings.

The check valve 42 inthe inlet chamber 31, as is more fully described inmy copending application Serial No. 362,180, flied October 22, 1940,comprises a sleeve-like cage 43 having a seat 44 formed thereon againstwhich is biased a valve plate 45 by a leaf-like spring structure 46centrally apertured to receive a stud structure 41 preferably anchoredto the valve plate 45, with,

spacing means 48 interposed between the valve plate structure 45 and-thespring structure 46 to formopposed abutments whereby the valve plate canbe biased to its seat and the parts of the valve assembled in the cage43 by a split-ring 49-, seated within a groove in the cage 43 andbearing against peripheral portions of the spring structure 46. The baseof the cage 43 is machined out at 50 to form a tapered throat for thevalveport; The check valve in the outlet chamber 40' is similar inconstruction to the check valve in the inlet chamber 31.

Pulsation eliminators may be provided in the inlet and outlet passagesby forming recesses 53, 53 in the caps 38 and 4i and trapping a body ofair therein by flexible diaphragms 54, 54 of resilient material, such asneoprene, each held in position on an annular seat 55 by a press-fittedring 56.

For the purposes of moving the operating rod l1 axially for hand primingor the like a shoulder 5'! is provided thereon by forming a hole 58through one leg of the roller fork. A radiallyextending boss 59 on thebase I0 is bored to receive rotatably a shaft 50 having acircumferentialgroove iii in which the end of a pin or set screw 62seats to hold the shaft in position. The inner end 63 of the shaft ismachined off on the top side thereof -to form a pair of camming portions64, 64 one of which is adapted to bear against the shoulder 51 when theshaft 50 is rotated in a clockwise or counter-clockwise directionthereby to lift the operating rod and flex the diaphragm inwardlya'gainst the biasing spring so as to raise the cam roller Hi from thecam 20. An operating arm 65 is keyed to the shaft 60 for rotating it anda coil spring 66 around the end of the shaft 60 having one end thereofanchored to the base member In and the other end thereof anchored to thearm 65 assures return of the arm-65 to a disengage position determinedby a stud 61 bearing against the edge of the casing l4. a

By way of example the transfer pump of the present invention mayvbemounted by means of mounting ears 68-68 on the base member 10 upon thecase of a high pressure injecting apparatus for feeding fuel to a Dieselengine. Such injecting apparatus may comprise a plurality of highpressure injecting pump devices, one for each cylinder of the engine,all operated by a common cam. The-circumferential surface of this cammay be provided with lobes equal in number to the number of highpressure injecting devices so that each revolution of the cam, such as20, will result in a number of complete transfer pump cycles equal tothe number of high pressure injecting devices each of which is oper-'ated during one cam revolution. Such operation obviously will be of veryhigh frequency and it has been found that the apparatus of the presentinvention with the provision of diaphragm travel of about .0125" oneach-side of the neutral position will perform its functions under suchconditions in a highly satisfactory manner. Itwill further be noted thatwith such a mounting of the device all of the parts thereof can easilyand readily be assembled from the top.

In operation when the operating rod is lifted upwardly by a cam theresultant inward flexin of the diaphragm against the biasing action ofthe spring structure minimizes the space of the pump chamber and whenthe cam permits the operating rod to be moved outwardly by the biasingspring structure partial vacuum is created in the pump chamber producinga differential in 7 pressure on opposite sides of the inletvalve'sufficient to open the same and cause fluid to flow into the pumpchamber. When the operating rod is again moved inwardly the inlet valveautomatically closes, and pressure built up in the pump chamber byinward flexing of the diaphragm causes the outlet-valve to unseat andfluid to be delivered through the outlet passage from the pump chamber.When the biasing spring structure' is against permitted to move thediaphragm outwardly the outlet valve automatically closes and the cycleis then repeated. The pump apparatus may be manually primed by flexingthe diaphragm inwardly and outwardly a number of times, which can beaccomplished by pulling on the priming arm, releasing it and repeatingthe operation. Operation of the transfer pump may be arrested by pullingon the priming arm and holding it.

Itwill thus be seen that the objects set forth above are eflicientlyattained by apparatus of the present invention and since certain changesmay be made in the above construction and different embodiments of'theinvention could be made without departing from the scope thereof, it isintended that all matter contained in the above description or shown inthe accompanying drawings shall be interpreted as illustrative and notin a limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features-of the invention hereindescribed, .-and all statements of the scope of the invention which, asa matter of language, migh be said to fall therebetween. 1

Having described my invention, what I clai as new and desire to secureby Letters Patent is:

1. Fluid transfer apparatus comprising, in combination, a basemember, acasing, a flexible diaphragm peripherally mounted on said casing to formtherewith a pump chamber, an operating member mounted on said diaphragmand projecting outwardly through said base member free from any bearingsupport and having a mechanical diaphragm-flexing mechanism-engagingportion, an engaging shoulder on the side of said operating member, anda manually rolower for mechanically flexing operation of said adiaphragm, resilient means biasing said diaphragm outwardly axially ofsaid rod, a shoulder on the side of said rod, a rotatable shaft mountedtransversely on said base plate with its inner end shaped to engage saidshoulder and move said rod axially inward to a'cam-disengaging positionwhen said shaft is rotated, and means to permit manual rotation of saidshaft.

3. Fluid transfer apparatus comprising, in

combination, casing structure, flexible diaphragm.

structure mounted on said casing structure to form therewith a pumpchamber, an operating member adapted to flex said diaphragm for pumpingaction and having a mechanical diaphragm-flexing mechanism-engagingportion, an engaging shoulder provided on said operating member by theformation of a transversely extending slot therein, and a shaftrotatably mounted on said casing structure and having an eccentric endportion received in the slot to engage said. shoulder for moving saidoperating member axially when said shaft is rotated.

biasing said diaphragm structure outwardly, an operating member adaptedto flex said diaphragm inwardly for pumping action, an engaging shoulderprovided on said operating member by the formation of a transverselyextending slot therein, and a shaft rotatably mounted on said casingstructure and having an eccentric end portion received in the slot toengage said shoulder for moving said operating member axially inwardlywhen said shaft is rotated.

5. Fluid transfer apparatus comprising, in combination, casingstructure, flexible diaphragm structure mounted on said casing structureto form therewith a pump chamber, resilient means biasing said diaphragmstructure outwardly, an operating vmember adapted to flex said diaphragminwardly for pumping action, an engaging shoulder provided on saidoperating member by the formation of a transversely extending slottherein, and a cylindrical shaft transversely mounted in a rotatablemanner on said casing structure with a side of the inner end thereofflatted off to provide a camming shoulder received in the slot to engagesaid flrst mentioned shoulder for moving said operating member axiallyinwardly when said shaft is rotated.

6. Fluid transfer apparatus comprising, in combination, a base plate, acasing, a flexible diaphragm peripherally supported between said plateand said casing to form with the latter a pump chamber, an operating rodmounted on said diaphragm and projecting outwardly through a hole insaid base plate and terminating in a cam follower, resilient meansbiasing said diaphragm outwardly axially of said rod, an engagingshoulder provided on said rod by the formation of a transverselyextending slot therein, a cylindrical shaft transversely mounted in arotatable manner on said base plate, said shaft having a side of theinner end thereof received in the slot and flatted off to provide acamming /shoulder adapted to engage said first mentioned 4. Fluidtransfer apparatus comprising, in

combination, casing structure, flexible diaphragm structure mounted onsaid casing structure to form therewith a pump chamber, resilient meansshoulder for moving said rod axially inwardly when said shaft isrotated, and means to rotate said shaft.

WARNER T. TABB.

